September 11, 2018

Do text message reminders help Class II correction?


We all hope that patients respond to reminders about their treatment. This new study shows that text messaging is effective. It is worth a careful read.

The results of our treatment depend upon the skill of the operator and the co-operation of our patients.  There have been recent developments in the use of reminders for patients using text messages and other forms of social media.  This interesting trial of text messaging that comes up with some very clinically relevant findings.

A team from Bauru, Brazil did this study. The Angle Orthodontist published it. This means that it is open access and anyone can access this paper.

The influence of text messages on the cooperation of Class II patients regarding the use of intermaxillary elastics

Simone Maria Massud Leone et al

Angle Orthodontist: Advance access

DOI: 10.2319/011218-31.1

They set out to answer this question:

“Do text reminders influence the cooperation of orthodontic patients’?

What did they do?

I think that they did a randomised controlled trial. The PICO was

Participants: Orthodontic patients with Class II malocclusion treated on a non-extraction basis. The Class II correction was achieved with Class II elastics.

Intervention:  Text message reminders

Control: Treatment as usual with no reminders

Outcome: Measurement of sagittal discrepancy of arches measured from study casts taken at the start of elastic wear (T1) and three months later (T2)

They included 42 patients in the study and divided them into two equal groups of 21 patients. They gave limited information on the randomisation sequence generation. I could not find any information on allocation concealment and consent. Their sample size calculation was clear.  They could not blind the operator and patient to treatment allocation. Nevertheless, the models were assessed blind.

They sent the  text messages via WhatsApp twice a week during the three month period of the study.

They measured the sagittal discrepancy of the buccal segments by placing marks on the study casts in the interdental spaces between the upper canine and first premolar and the lower second premolar and first molar. Then they measured the distance between these points using digital calipers.  Finally, they carried out simple univariate statistical tests between the groups.

What did they find?

Firstly, they found that their method of measurement was reproducible with a mean error of 0.03-0.09 mm. They presented several measurements in their results. I decided to concentrate on the final measurement for the control and intervention groups.

When we are interpreting the results of a trial, the most simple approach is to consider the final values of the outcome measure. For this study, the mean distance between the marks (degree of Class II) for the experimental group was 15.35 (SD=1.33) and for the control it was 16.7mm. This resulted in a difference of 1.42mm. This was statistically significant. I have  included this data in this simple table.

Experimental Control Difference
Mean distance (mm) 15.35 (14.7-15.9) 16.7 (16.3-17.3) 1.42 (0.59-2.2)

They also suggested that the text reminder group showed a Class II correction that was greater than 3.7 times that of the control.

What did I think?

I thought that this was an interesting study. The main strengths were that the authors attempted to ask a clinically relevant question using trial methodology. I also thought that their method of measuring the effect of cooperation  was neat, simple and clinically relevant.  This was a great alternative to measuring elastic wear as they measured the results of the intervention/treatment. We should consider whether this method was accurate as this relies on correct orientation of models. They did not seem to assess this. However, we must assume that they used the same method for both groups and this should not influence the results.

I was disappointed that I could not find many details of the randomisation and concealment. This is very important because we need to see how this was done to assess the possibility of bias in the study.  This is also a requirement of the CONSORT statement on the reporting of randomised trials and I am not sure if the Angle Orthodontist has signed up to this?  

Finally, the authors claim that the text messaging resulted in a greater than 3.7 times Class II correction. Whenever someone reports this we should look at the effect size. In this study it was 1.4 mm and we may feel that this is clinically significant. Nevertheless, when we look at the confidence interval of the difference, I think that this is rather wide. This means that we need to interpret this data with a degree of caution.

Overall, I think that this study shows that there may be an effect of reminders on cooperation.   I may try this to see if I can get increased levels of co-operation in my patients.

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Have your say!

  1. Avatar

    Very clinically relevant study. We undertook a systematic review to assess the effectivensss of reminder therapy in orthodontics which was published in the EJO, one of the included RCTs was your paper.
    We concluded that “There is moderate-to-high quality of evidence that reminders have a positive effect on OH and adherence to appointments in orthodontic patients. These effects were demonstrated in the short- and long-term. Future high-quality RCTs should be designed with longer follow-up periods.”

  2. Avatar

    We have been using a very simple and effective elastic reminder texting system for over 5 years with similar results to what this study found. The system is called Orthodontext. It’s super simple to implement, requires almost zero training for your team and it can be accessed directly through a link on your desktop. It does not require the patient or the practice to download an app, there is no portal that the practice has to log into each day, patients are able to change the times and frequency of when they receive their text messages themselves, and can turn them off when their treatment is over. They can do all that without having to log in or remember a password. It is completely passwordless. It also requires less than 30 seconds to enter a patient, actually, the patient does it themselves (which is essential for patient buy-in). We send over 20,000 texts a month with almost no effort at a very reasonable price. Many patients request more elastics by replying to the text (which goes to an office email) and my team send them in the mail. Parents love it. We also use it for many other types of reminders like brushing or when to change aligners. We also send “care” texts after specific procedures which has been very well received. Another great feature is that when a patient responds, the response goes to an office email and a team member can reply to the email and it goes back to the patient as a text. You should check it out at:

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